Documentation/How Tos/Calc: ACOS function

ACOS

Returns the inverse cosine (the arccosine) of a number.

Syntax:

ACOS(number)

ACOS returns the inverse trigonometric cosine of number, in other words the angle (in radians) whose cosine is number. The angle returned is between 0 and PI.

To return the angle in degrees, use the DEGREES function.

Example:

ACOS(-1)

returns 3.14159265358979 (PI radians).

DEGREES(ACOS(0.5))

returns 60. The cosine of 60 degrees is 0.5.

See also:

COS, SIN, TAN, COT,

ASIN, ATAN, ATAN2, ACOT

DEGREES, PI

Mathematical functions